Endoscope for tissue dissection and visualization

ABSTRACT

One aspect of the present disclosure relates to an endoscope for facilitating a medical procedure by creating an anatomic space in or adjacent a target bodily tissue to be imaged. The endoscope can comprise a flexible, elongate tubular member defining a central lumen and an expandable dissecting member coupled to a distal end of the tubular member. The tubular member can further include at least one imaging channel extending longitudinally therethrough. The at least one imaging channel can include a visualization system for conveying an image from the distal end of the tubular member to a user. The expandable dissecting member can define a channel in fluid communication with the central lumen of the tubular member. The expandable dissecting member can extend beyond the distal end of the tubular member.

RELATED APPLICATION

This application is a Continuation of U.S. patent application Ser. No.14/480,935, filed Sep. 9, 2014, which claims the benefit of U.S.Provisional Patent Application Ser. No. 61/875,413, filed Sep. 9, 2013,the entirety of both are incorporated herein by reference for allpurposes.

TECHNICAL FIELD

The present disclosure relates generally to a surgical instrument andmethod for visualizing a target bodily tissue and, more particularly, toan endoscope for tissue dissection to provide an adequate depth of fieldfor fiberoptic viewing.

BACKGROUND

Surgeons in the past have used blunt-tipped instruments as well asballoons in connection with endoscopic surgery to dissect tissue anddevelop a working space in the interior of the body. Typically, thedevelopment of such a working space is done blindly or under endoscopicviewing only if at least one accessory port or accessway is established.To perform a surgery in such a working space, the working space ismaintained by insufflation with carbon dioxide gas, which provides roomfor viewing with an endoscope as well as room for manipulating accessoryinstruments. To introduce such accessory instruments into the workingspace, additional incisions typically are made by plunging asharp-tipped trocar through the distended body wall overlying theinsufflated working space.

It has been found that it may be undesirable to dissect accessways andanatomic spaces blindly. It also has been found that it may be difficultto make additional incisions into a dissected anatomic space,particularly if of limited volume or if overlying delicate anatomicstructures. Additionally, it has been found that insufflation of aworking space with carbon dioxide causes tissue emphysema, which may beundesirable for particular patients because of excessive carbon dioxideabsorption into the blood, thus making a minimally invasive endoscopicapproach unsuitable.

SUMMARY

The present disclosure relates generally to a surgical instrument andmethod for visualizing a target bodily tissue and, more particularly, toan endoscope for tissue dissection to provide an adequate depth of fieldfor fiberoptic viewing.

One aspect of the present disclosure relates to an endoscope forfacilitating a medical procedure by creating an anatomic space in oradjacent a target bodily tissue to be imaged. The endoscope can comprisea flexible, elongate tubular member defining a central lumen and anexpandable dissecting member coupled to a distal end of the tubularmember. The tubular member can further include at least one imagingchannel extending longitudinally therethrough. The at least one imagingchannel can include a visualization system for conveying an image fromthe distal end of the tubular member to a user. The expandabledissecting member can define a channel in fluid communication with thecentral lumen of the tubular member. The expandable dissecting membercan extend beyond the distal end of the tubular member

Another aspect of the present disclosure relates to an endoscope forfacilitating a medical procedure by creating an anatomic space in oradjacent a target bodily tissue to be imaged. The endoscope can comprisea flexible, elongate tubular member and an expandable dissecting membercoupled to a distal end of the tubular member. The tubular member canfurther include at least one imaging channel extending longitudinallytherethrough. The at least one imaging channel can include avisualization system for conveying an image from the distal end of thetubular member to a user. The expandable dissecting member cancompletely envelope, and extend beyond, the distal end of the tubularmember.

Another aspect of the present disclosure relates to a method forvisualizing a target bodily tissue of a patient during a medicalprocedure. One step of method can include providing an endoscopecomprising a flexible, elongate tubular member and an expandabledissecting member coupled to a distal end thereof. The tubular membercan further include a visualization system for conveying an image fromthe distal end of the tubular member to a user. The endoscope can beinserted into the patient with the expandable dissecting member in adeflated configuration. Next, the distal end of the tubular member canbe advanced towards the target tissue. The dissecting member can then beinflated to create an anatomic space in or adjacent the target tissue.The visualization system can be operated to convey an image of thetarget tissue from the distal end of the tubular member to the user.

BRIEF DESCRIPTION OF THE DRAWINGS

The foregoing and other features of the present disclosure will becomeapparent to those skilled in the art to which the present disclosurerelates upon reading the following description with reference to theaccompanying drawings, in which:

FIG. 1A is a perspective view of an endoscope and associated imagingcomponents constructed in accordance with one aspect of the presentdisclosure;

FIG. 1B is a cross-sectional view taken along Line 1B-1B in FIG. 1A;

FIG. 1C is a schematic illustration showing a front view of the distalend of the endoscope in FIGS. 1A-B;

FIG. 2 is a perspective view showing an alternative construction of anexpandable dissecting member comprising the endoscope in FIGS. 1A-C;

FIGS. 3A-B are cross-sectional views similar to FIG. 1B showingoperation of a translation mechanism according to another aspect of thepresent disclosure;

FIG. 4A is a perspective view showing an alternative configuration ofthe endoscope in FIGS. 1A-C;

FIG. 4B a cross-sectional view taken along Line 4B-4B in FIG. 4A; and

FIG. 5 is a process flow diagram illustrating a method for visualizing atarget bodily tissue of a patient during a medical procedure accordingto another aspect of the present disclosure.

DETAILED DESCRIPTION

Definitions

Unless defined otherwise, all technical and scientific terms used hereinhave the same meaning as is commonly understood by one of skill in theart to which the present disclosure pertains.

In the context of the present disclosure, the singular forms “a,” “an”and “the” can include the plural forms as well, unless the contextclearly indicates otherwise. It will be further understood that theterms “comprises” and/or “comprising,” as used herein, can specify thepresence of stated features, steps, operations, elements, and/orcomponents, but do not preclude the presence or addition of one or moreother features, steps, operations, elements, components, and/or groupsthereof.

As used herein, the term “and/or” can include any and all combinationsof one or more of the associated listed items.

As used herein, the term “and/or” can include any and all combinationsof one or more of the associated listed items.

As used herein, phrases such as “between X and Y” and “between about Xand Y” can be interpreted to include X and Y.

As used herein, phrases such as “between about X and Y” can mean“between about X and about Y.”

As used herein, phrases such as “from about X to Y” can mean “from aboutX to about Y.”

It will be understood that when an element is referred to as being “on,”“attached” to, “connected” to, “coupled” with, “contacting,” etc.,another element, it can be directly on, attached to, connected to,coupled with or contacting the other element or intervening elements mayalso be present. In contrast, when an element is referred to as being,for example, “directly on,” “directly attached” to, “directly connected”to, “directly coupled” with or “directly contacting” another element,there are no intervening elements present. It will also be appreciatedby those of skill in the art that references to a structure or featurethat is disposed “adjacent” another feature may have portions thatoverlap or underlie the adjacent feature.

Spatially relative terms, such as “under,” “below,” “lower,” “over,”“upper” and the like, may be used herein for ease of description todescribe one element or feature's relationship to another element(s) orfeature(s) as illustrated in the figures. It will be understood that thespatially relative terms can encompass different orientations of theapparatus in use or operation in addition to the orientation depicted inthe figures. For example, if the apparatus in the figures is inverted,elements described as “under” or “beneath” other elements or featureswould then be oriented “over” the other elements or features.

It will be understood that, although the terms “first,” “second,” etc.may be used herein to describe various elements, these elements shouldnot be limited by these terms. These terms are only used to distinguishone element from another. Thus, a “first” element discussed below couldalso be termed a “second” element without departing from the teachingsof the present disclosure. The sequence of operations (or steps) is notlimited to the order presented in the claims or figures unlessspecifically indicated otherwise.

As used herein, the term “endoscope” can refer to any type of invasiveinstrument, flexible or rigid, having scope features. These include, butare not limited to, microendoscopes, colonoscopes, gastroscopes,laparoscopes and rectoscopes.

As used herein, the term “microendoscope” can refer to an endoscopehaving a small diameter, such as less than about 3 mm.

Overview

The present disclosure relates generally to a surgical instrument andmethod for visualizing a target bodily tissue and, more particularly, toan endoscope for tissue dissection to provide an adequate depth of fieldfor fiberoptic viewing. As illustrated in FIGS. 1A-C, one aspect of thepresent disclosure can include an endoscope 10 for facilitating amedical procedure by creating an anatomic space in or adjacent a targetbodily tissue to be imaged. The endoscope 10 of the present disclosureis a low-cost, flexible fiberoptic scope that can be used to visualizeor image a variety of target bodily tissues during any number ofminimally invasive or less invasive medical procedures. The endoscope 10can be used alone or in conjunction with other medical devices,depending upon its intended application. For example, the endoscope 10can be used as part of, or in conjunction with, an endotrachealintubation tube (not shown) or laryngeal mask (not shown) to permit ananesthesiologist to scope, intubate, and monitor during anesthesia andintubation of a patient's trans-laryngeal and tracheal airway. Otherapplications of the endoscope 10, as well as advantages of the presentdisclosure, are discussed in more detail below.

Certain aspects of the present disclosure can facilitate transvascular,minimally invasive, and other “less invasive” medical procedures byproviding direct visualization of a target bodily tissue. The phrase“less invasive” can mean any procedure that is less invasive thantraditional, large-incision open medical or surgical procedures. Forexample, a less invasive procedure may be an open surgical procedureinvolving one or more smaller incisions, a transvascular or percutaneousprocedure, a transvascular procedure via cut-down, a laparoscopicprocedure, or the like. Generally, any medical procedure in which a goalis to minimize or reduce invasiveness to the patient may be consideredless invasive. Although the terms “less invasive” and “minimallyinvasive” may sometimes be used interchangeably in this application,neither these nor other descriptive terms should be interpreted to limitthe scope of the present disclosure. Generally, the present disclosuremay be used in performing or enhancing any suitable medical procedure,such as laparoscopic or other endoscopic procedures on any part of thebody.

Endoscopes

One aspect of the present disclosure includes an endoscope 10 forfacilitating a medical procedure by creating an anatomic space in oradjacent a target bodily tissue to be imaged. As shown in FIG. 1A, theendoscope 10 can comprise a flexible, elongate tubular member 12 and anexpandable dissecting member 14 coupled to a distal end 16 of theelongate tubular member. In one example, the endoscope 10 can be amicroendoscope.

To facilitate operation of the endoscope 10 during a medical procedure,various imaging components 18 may be associated with the endoscope.Examples of such imaging components 18, whose operation is discussed inmore detail below, can include a vacuum or suction source 20, a fluidsource 22, a processor 24 or visualization control system, and a display26 or image viewer. Although the endoscope 10 is described herein asincluding an expandable dissecting member 14, it will be appreciatedthat certain aspects of the present disclosure may include an endoscopethat is free of an expandable dissecting member. In such instances, theendoscope 10 may be associated with one or more medical devices, such asan endotracheal intubation tube or laryngeal mask, or, alternatively,the endoscope may be used as a standalone device.

In another aspect, the elongate tubular member 12 can include a proximalend 28, a distal end 16 having a size and shape for insertion into apatient's body, and a central lumen 30 (FIG. 1B) extending between theproximal and distal ends. A longitudinal axis LA can extend parallel, orsubstantially parallel to, the central lumen 30. In some instances, thecentral lumen 30 can be defined by an inner surface 32 of the elongatetubular member 12. It will be appreciated that the elongate tubularmember 12 can include two or more lumens extending longitudinallytherethrough or, alternatively, that the elongate tubular member may bea solid structure that is free of any longitudinally-extending lumens.The elongate tubular member 12 (FIG. 1A) may be substantially flexible,semi-rigid, and/or rigid along its length, and may be formed from avariety of materials, including plastic, metal, and/or compositematerials. For example, the elongate tubular member 12 may besubstantially flexible at the distal end to facilitate advancementthrough tortuous anatomy, and/or may be semi-rigid or rigid at theproximal end 28 to enhance pushability of the endoscope 10 withoutsubstantial risk of buckling or kinking.

In some instances, the elongate tubular member 12 can be steerable,e.g., the distal end 16 may be controllably deflected transverselyrelative to the longitudinal axis LA. In such instances, a singlepullwire (not shown) or other steering element may be provided (e.g.,within a lumen) for steering the distal end 16 in one transverse plane(thereby providing one degree of freedom). Alternatively, two pullwiresmay be provided for steering the distal end 16 in two orthogonal planes(thereby providing two degrees of freedom). The pullwire(s) can includea cable, wire, band, or the like, that may be slidably disposed within alumen. The pullwire(s) may be attached or otherwise fixed relative tothe elongate tubular member 12 at a location adjacent the distal end 16,e.g., offset radially outwardly from the longitudinal axis LA. Thus,when a pullwire is pulled proximally (e.g., from the proximal end 28 ofthe elongate tubular member 12) a bending force may be applied to thedistal end 16, causing the distal end to bend transversely relative tothe longitudinal axis LA.

The elongate tubular member 12 may also include a handle (not shown) orother control mechanism coupled to or otherwise provided on the proximalend 28 thereof. In such instances, the handle can have a shape, size,and/or contour to facilitate tactile manipulation the elongate tubularmember 12 during use. In some instances, the handle can include one ormore steering controls that may be actuated to steer the distal end 16of the elongate tubular member 12. For example, a dial (not shown) maybe provided that may be coupled to a pullwire. The dial may be rotatedto apply a proximal force on the pullwire, thereby bending the distalend 16 of the elongate tubular member 12. The handle may also includeports and/or other connections for connecting one or more of the imagingcomponents to the elongate tubular member 12.

It will be appreciated that any known connector(s) may be provided forpermanently or temporarily connecting components (e.g., imagingcomponents 18) to the elongate tubular member 12. For example, a Luerlock connector (not shown) may be used to connect tubing or otherfluid-conveying components to the elongate tubular member 12. A syringe(not shown) or other source of fluid, e.g., including saline, carbondioxide, nitrogen, or air, may be connected via tubing (not shown) tothe elongate tubular member 12. In such instances, the syringe may alsoprovide a source of vacuum for deflating the expandable dissectingmember 14. Another source of fluid (not shown), e.g., saline, and/or atherapeutic or diagnostic agent, may be connected via tubing (not shown)to the elongate tubular member 12 for delivering fluid beyond the distalend 16 thereof.

In another aspect, the elongate tubular member 12 can include at leastone imaging channel 34 (FIG. 1C) that extends longitudinallytherethrough. In some instances, the imaging channel 34 can be embeddedwithin the wall 36 of the elongate tubular member 12, which is definedby the inner surface 32 and an outer surface 38 thereof. Although notshown in detail, the imaging channel 34 can include oppositely disposedopenings that are concentric with the proximal and distal ends 28 and 16of the elongate tubular member 12. The imaging channel 34 can becircumferentially disposed about the central lumen 30 of the elongatetubular member 12. The imaging channel 34 can have a circularcross-sectional profile; however, it will be appreciated that othercross-sectional profiles are possible (e.g., ovoid, square, rectangular,etc.). Where the elongate tubular member 12 includes two or more imagingchannels 34, the imaging channels can have the same or differentcross-sectional profiles and/or the same or different dimensions (e.g.,radii).

It will be appreciated that the elongate tubular member 12 can includeother channels extending therethrough. In one example, the elongatetubular member 12 can include an inflation channel (not shown) fordelivering an inflation medium to the expandable dissecting member 14.In such instances, the inflation channel can be embedded within the wall36, beginning at the proximal end 28 of the elongate tubular member 12and extending distally until a distal opening thereof is in fluidcommunication with an interior chamber 40 of the expandable dissectingmember 14. In another example, the elongate tubular member 12 caninclude a working channel (not shown) for positioning or delivering oneor more instruments (not shown) to a target bodily tissue. Any suitableinstrument(s) may be passed through the working channel, such as asurgical clip applier, an ablation device, a suturing device, and thelike.

The imaging channel 34 can include a visualization system (not shown indetail) for conveying an image from the distal end 16 of the elongatetubular member 12 to a user. Generally, the visualization system caninclude any one or combination of imaging devices that enable directvisualization of a target bodily tissue during use of the endoscope 10.In one example, the visualization system can include an imaging element(not shown) and a lighting element (not shown) disposed within first andsecond imaging channels, respectively. In some instances, the imagingelement can comprise an optical fiber and include another imagecapturing element (e.g., at its distal end), such as acharge-coupled-device (CCD), CMOS, infrared imaging chip and/or otherdevice to capture, digitize, and/or otherwise convert images intoelectrical signals that may be transferred to a processor 24 and/ordisplay 26. In some instances, the imaging element can comprise a lens,filter, mirror, or other structure configured to control the field ofview or focal length thereof. The utilization of an imaging elementlocated at the distal end 16 of the elongate tubular member 12 forpurposes of visualizing objects from a point of interest is referred toherein as “direct visualization”. In other words, “direct visualization”can refer to placing an imaging “eye” proximate to a target bodilytissue.

In other instances, the lighting element can be operably paired with theimaging element to provide illumination or radiation appropriate forcapturing images of a target bodily tissue. Where the imaging elementcomprises an optical fiber, for example, the lighting element caninclude an emitter of light, such as a small light bulb, alight-emitting diode, an incandescent light source, or end of anotheroptical fiber. The visualization system, including the imaging andlighting elements, can be coupled (e.g., by a cable) to one or moreelectronic components for processing and/or displaying images of thetarget bodily tissue. Examples of such electronic components can includecomputers or other display or capture devices, such as a laptopcomputer, handheld or PDA devices, a computer terminal, a LCD display,standard video monitor, and the like, to display and/or store the imagesacquired from the visualization system. Optionally, the computer (orother capture device) may provide electrical power to the visualizationsystem.

In another aspect, the elongate tubular member 12 can include anexpandable dissecting member 14 coupled to the distal end 16 thereof. Asdiscussed in more detail below, the expandable dissecting member 14 canbe used to dissect tissue along an anatomic plane under directvisualization. Use of the expandable dissecting member 14 can provide adissected optical cavity or anatomic space in or adjacent a targetbodily tissue to provide adequate depth of field for endoscope viewingby generally applying forces perpendicular to tissue being treated.Consequently, use of the expandable dissecting member 14 during amedical procedure not only provides adequate depth of field, but alsoremoves the need for insufflation with carbon dioxide, which can pose ahealth hazard to the patient.

The dissecting member 14 may be expandable from a contracted or deflatedcondition (not shown) to an enlarged or expanded condition when aninflation fluid is introduced into the interior chamber 40 of thedissecting member. For example, a substantially transparent inflationfluid (e.g., saline, carbon dioxide, nitrogen, air, and the like) can bedelivered through an inflation channel of the elongate tubular member 12into the interior chamber 40 of the expandable dissecting member 14. Asused herein, the term “transparent” can refer to any material and/orfluid that may permit sufficient light to pass therethrough in order toidentify or otherwise visualize bodily tissues or structures through thematerial and/or fluid. The term “light” can refer to light radiationwithin the visible spectrum, but may also include other spectra, such asinfrared or ultraviolet light. In some instances, the expandabledissecting member 14 can be permanently affixed on or near the distalend 16 of the tubular elongate member 12. For example, a proximal end 39of the expandable dissecting member 14 can be affixed to the outersurface 38 of the elongate tubular member 12 using an adhesive, heating,sonic welding, an interference fit, and/or an outer sleeve (not shown).

In one example, the expandable dissecting member 14 can comprise acompliant balloon. In such instances, the expandable dissecting member14 can be made of compliant and/or elastomeric materials, such assilicone, latex, isoprene and chronoprene. In another example, theexpandable dissecting member 14 can comprise a non-compliant balloon andbe formed, for instance, from a substantially non-compliant material,such as polytetrafluoroethylene, expanded polytetrafluoroethylene,fluorinated ethylenepropylene, polyethylene teraphathalate, urethane,olefins, and/or polyethylene, such that the expandable dissecting membermay expand to a predetermined shape when fully inflated. In suchinstances, the expandable dissecting member 14 may be sufficientlynon-compliant to displace tissue and facilitate creation of an anatomicspace in or adjacent a target bodily tissue.

In the expanded or enlarged condition, the dissecting member 14 can havea generally annular shape and define a channel 42 (FIG. 1B) that is influid communication with the central lumen 30 of the elongate tubularmember 12. The term “fluid communication” can refer to a pathway thatallows the passing of a fluid and/or light and/or an instrument betweenthe central lumen 30 of the elongate tubular member 12 and the channel42 of the dissecting member 14. In one example, a distal end portion 44of the expandable dissecting member 14 can have a toroidal or “donut”shape such that the distal end portion encircles, and overhangs, thedistal end 16 of the elongate tubular member 12. In such instances, thetoroidal distal end portion 44 of the expandable dissecting member 14can create a circumferential channel 42 or lumen through which a targetbodily tissue can be directly visualized, a fluid can be delivered oraspirated, and/or an instrument can be delivered. In this configuration,the distal end portion 44 of the dissecting member 14 can form a concavesurface out of which a field of view of the visualization system extendsdistally.

The distal end 16 of the elongate tubular member 12 can be axiallyspaced apart from an opening of the channel 42 such that the distal endis not flush or concentric with the opening. Depending upon theconfiguration of the expandable dissecting member 14, it will beappreciated that the field of view of the visualization system may notinclude portions of the dissecting member. It will also be appreciatedthat the expandable dissecting member 14 can have a variety of differentshapes when inflated, such as a cylindrical or “hot dog bun” shape (FIG.2).

Advantageously, the presence of the channel 42 permits visualization ofan anatomical tissue or space abutting the distal end portion 44 of thedissecting member 14. This would not be possible if the distal end 16 ofthe elongate tubular member 12 were flush or concentric with the distalend portion 44 because the imaging surface would be pressed against thetissue, thus removing adequate depth of field for endoscopic viewing.The channel 42 thus makes the endoscope 10 extremely versatile anduseful in highly confined anatomical regions where excessive endoscopemovement and dissection is not possible.

In another aspect, the endoscope 10 can additionally or optionallyinclude a translation mechanism (not shown in detail) configured topermit selective translation of a portion of the elongate tubular member12 through the channel 42 defined by the expandable dissecting member14. As shown in FIGS. 3A-B, the translation mechanism allows a user toadvance or retract the elongate tubular member 12 in a longitudinaldirection (indicated by arrow) relative to the expandable dissectingmember 14. In doing so, the dimensions of the channel 42 (e.g., lengthand volume) can be increased or decreased for different purposes. Forexample, the length of the channel 42 can be increased by advancing theelongate tubular member 12 in a proximal direction to create a narrowerfield of view. Alternatively, the length of the channel 42 can bedecreased by advancing the elongate tubular member 12 in a distaldirection to increase the field of view.

An alternative construction of the endoscope 10 is shown in FIGS. 4A-B.The endoscope 10′ in FIGS. 4A-B can be identically constructed as theendoscope 10 in FIGS. 1A-C, except that the expandable dissecting member14′ of the endoscope 10′ is configured to completely envelop, and extendbeyond, the distal end 16 of the elongate tubular member 12 (e.g., whenthe dissecting member is in its expanded or enlarged condition). Inother words, the expandable dissecting member 14′ does not include achannel 42 that directly contacts, or is in fluid communication with, aportion of the elongate tubular member 12 (e.g., the central lumen 30).In this configuration, the expandable dissecting member 14′ can be madefrom one or more substantially transparent materials (such as thosediscussed above), and can be selectively filled with a substantiallytransparent inflation medium (also discussed above). Also in thisconfiguration, the elongate tubular member 12 may not include a centrallumen 30 and, instead, only include a visualization system as describedabove. In one example, the endoscope 10′ can comprise a microendoscope.

Another aspect of the present disclosure includes a method 46 (FIG. 5)for visualizing a target bodily tissue of a patient during a medicalprocedure. The method 46 can find use in visualizing a variety of targetbodily tissues during a medical or surgical procedure, such as anytransvascular, percutaneous, minimally invasive, and other less invasivemedical procedure. Accordingly, a variety of target bodily tissues canbe imaged including, but not limited to, digestive tract tissue,pulmonary tract tissue, cardiac tissue, muscle, tendons, cartilage, andfat tissue. As shown in FIG. 5 and described in more detail below, themethod 46 of the present disclosure can generally include the followingsteps: providing an endoscope 10 or 10′ (Step 48); inserting theendoscope into a patient (Step 50); advancing the endoscope towards atarget bodily tissue of the patient (Step 52); creating an anatomicspace in or adjacent the target bodily tissue (Step 54); and visualizingthe target bodily tissue (Step 56).

Step 48 of the method 46 can include providing an endoscope 10 or 10′.Depending upon the particular application (e.g., the target bodilytissue to be imaged), an endoscope 10 or 10′ as shown in FIGS. 1A-C orFIGS. 4A-B (respectively) can be used. Also depending upon theparticular application, the dimensions of the endoscope 10 or 10′ can betailored accordingly. For example, an expandable dissecting member 14having of a relatively small size can be selected where the targetbodily tissue is located in an area constrained by surroundinganatomical structures (e.g., bones). Additionally, the endoscope 10′shown in FIGS. 4A-B may be selected for use where delivery ofinstruments, fluids, etc. is not required. For illustrative purposesonly, the method 46 will be described using the endoscope 10 of FIGS.1A-C.

Once a suitable endoscope 10 has been selected, the endoscope can beinserted into the patient (Step 50). The insertion point for theendoscope 10 will depend upon the particular target bodily tissue to beimaged, as well as other factors, such as the age and health of thepatient. The endoscope 10 can be inserted into the patient with theexpandable dissecting member 14 in the collapsed or deflatedconfiguration. In one example, the distal end 16 of the elongate tubularmember 12 can be inserted into an oral or nasal airway of the patient.In another example, the distal end 16 of the elongate tubular member 12can be inserted into a blood vessel of the patient. In yet anotherexample, the distal end 16 of the elongate tubular member 12 can bepercutaneously inserted into a tissue (e.g., fat or muscle) of thepatient. It will be appreciated that the endoscope 10 can be insertedusing conventional image guidance modalities and/or under local orgeneral anesthesia.

At Step 52, the distal end 16 of the elongate tubular member 12 can beadvanced (e.g., under tactile or robotic control) towards the targetbodily tissue. For example, the distal end 16 of the elongate tubularmember 12 can be advanced immediately adjacent to, or into directcontact with, the target bodily tissue. Once the distal end 16 isappropriately positioned in or about the target bodily tissue, aninflation medium (e.g., air or saline) can be delivered to the interiorchamber 40 of the expandable dissecting member 14 (Step 54). As theinflation medium is delivered to the interior chamber 40, the radius ofexpandable dissecting member 14 can increase such that the outer surfaceof the dissecting member generally applies forces perpendicular to thebodily tissue overlying the dissecting member. The perpendicular forces,in turn, can displace the surrounding bodily tissue and create ananatomic space. Consequently, the created anatomic space can provide anincreased depth of field for endoscopic viewing. Depending upon thedesired field of view, the size of the expandable dissecting member 14can be adjusted by increasing or decreasing the amount of inflationmedium delivered to the interior chamber 40.

With the dissecting member 14 in the expanded or enlarged configuration,the visualization system can then be operated to convey one or moreimages of the target bodily tissue from the distal end 16 of theelongate tubular member 12 to the user. Direct visualization provided bythe endoscope 10 allows the user to easily view anatomic landmarks andstructures. If desired, the user can perform a procedure on the targetbodily tissue by, for example, advancing a surgical tool through aworking channel of the elongate tubular member 12, delivering atherapeutic fluid through the central lumen 30 of the elongate tubularmember, or removing a bodily fluid through the central lumen.Advantageously, the method 46 permits a user to directly visualize atarget bodily tissue without the need to dissect surrounding tissueusing potentially harmful gases, such as carbon dioxide. Consequently,the risk of embolism during and after the medical procedure iseliminated by the method.

From the above description of the present disclosure, those skilled inthe art will perceive improvements, changes and modifications. Suchimprovements, changes, and modifications are within the skill of thosein the art and are intended to be covered by the appended claims. Allpatents, patent applications, and publication cited herein areincorporated by reference in their entirety.

The following is claimed:
 1. An endoscope for facilitating a medicalprocedure by creating an anatomic space in or adjacent a target bodilytissue to be imaged, the endoscope comprising: a flexible, elongatetubular member having a distal end, an inner circumferential surface, anouter circumferential surface and a central lumen extending within theinner circumferential surface, the central lumen extending coaxiallywith a central longitudinal axis of the elongate tubular member, thetubular member further including a plurality of imaging channelsextending longitudinally therethrough, each of the imaging channelsincluding at least a portion of a visualization system for conveying animage from the distal end of the tubular member to a user, wherein awall of the tubular member is defined by the inner circumferentialsurface and the outer circumferential surface, and wherein the imagingchannels are embedded within the wall and are circumferentially disposedabout the central lumen; and an expandable dissecting member coupled tothe distal end of the tubular member, the expandable dissecting memberdefining a channel in fluid communication with the central lumen of thetubular member, wherein the distal end of the elongate tubular member isaxially spaced apart from and not flush with an opening of the channelof the expandable dissecting member located at the distal end portion ofthe expandable dissecting member; wherein a distal end portion of theexpandable dissecting member obtains a toroidal shape when theexpandable dissecting member is expanded such that the distal endportion encircles, and overhangs, the distal end of the elongate tubularmember; and wherein positioning of at least one of the imaging channelsbeing configured so that a total field of view of the visualizationsystem does not include a distal portion of the expandable dissectingmember when the expandable dissecting member is expanded.
 2. Theendoscope of claim 1, wherein the expandable dissecting member isdesigned to not be removable from the distal end of the tubular member.3. The endoscope of claim 1, wherein the expandable dissecting member isa compliant balloon.
 4. The endoscope of claim 1, wherein the pluralityof imaging channels at least comprises first and second imaging channelsand wherein the visualization system further comprises: an imagingelement disposed within the first imaging channel; and a lightingelement disposed within the second imaging channel; wherein each of thefirst and second imaging channels is disposed circumferentially aboutthe central lumen of the tubular member.
 5. The endoscope of claim 4,wherein the imaging element is an optical fiber.
 6. The endoscope ofclaim 4, wherein the lighting element comprises a structure selectedfrom the group consisting of an incandescent light source, alight-emitting diode, and an optical fiber.
 7. The endoscope of claim 1,wherein the distal end portion of the expandable dissecting member formsa concave surface out of which the field of view of the visualizationsystem extends distally.
 8. The endoscope of claim 1, being amicroendoscope.
 9. The endoscope of claim 1, wherein a diameter of thecentral lumen is larger than diameters of the imaging channels.
 10. Theendoscope of claim 1, wherein the imaging channels are spacedcircumferentially about the central lumen, the imaging channels beingspaced evenly relative to one another in a circumferential direction.